Clinical Trial Tests Electrical Current for Treatment Of Migraines

By Bonnie Prescott
Beth Israel Deaconess Medical Center staff

One theory behind the pain of migraine headaches is that overloaded brain circuits cause parts of the brain to become hyperactive - and hypersensitive - to everyday sights, sounds and smells. And once this hyperactivity is triggered in one area of the brain, it can affect the functioning of other brain areas that are related to pain. The end result is often debilitating.

Now researchers at the Berenson-Allen Center for Noninvasive Brain Stimulation at Beth Israel Deaconess Medical Center (BIDMC) are testing an experimental migraine treatment that interrupts these overloaded brain circuits by literally jolting the brain with a weak electric current capable of altering brain activity.

Called transcranial direct current stimulation (tDCS), the technology is currently being tested in a clinical trial of 24 individuals suffering from chronic migraines (defined as 15 or more headaches per month.) "Our preliminary analysis shows that the patients showed signs of improvement after 10 tDCS sessions," says BIDMC neuroscientist Felipe Fregni, MD, PhD, the study's principal investigator.

"tCDS is a targeted experimental treatment in which brain areas can be either activated or deactivated in response to stimulation," explains Fregni. "One interesting aspect of this technology is that it has been in use for at least 200 years and is based on a simple circuit that generates a constant electrical current which flows between two electrodes. In fact, the source of energy is a 9-volt battery." But, he adds, only in the last decade have researchers understood the mechanisms of action behind this technology.

The rationale for using tCDS to treat migraines lies in the fact that the brain's neurons are constantly receiving electrical input from surrounding cells and subsequently sending pulses of voltage along to connecting neurons. In order to slow these rapidly firing brain cells, Fregni attaches electrodes to a subject's scalp. A small electrical current of 1mA is then passed through the brain, "calming down" the afflicted areas and making neurons less likely to fire.

"We are still running this investigation testing the effects of tDCS on chronic migraine" says Fregni. "If our results show positive outcomes, our next step will be to test the technology in a larger clinical trial."

For more information about this trial, contact the Berenson-Allen Center for Noninvasive Brain Stimulation at 617-667-0203.